Method and system for controlling electrolyte flow of flow battery

Abstract

The invention relates to a flow battery electrolyte flow control method and system. The method comprises the following steps: acquiring initial parameter data of a flow battery; the initial target flow of the electrolyte is determined; according to the initial target flow of the electrolyte and the initial parameter data of the flow battery, the initial target working frequency of a circulating pump is obtained through a preset flow fitting model, and the circulating pump is driven to work at the initial target working frequency; continuously collecting real-time parameter data of the flow battery, and updating the real-time flow of the electrolyte through the flow fitting model; continuously updating the real-time target flow of the electrolyte; and continuously updating the real-time target working frequency through the flow fitting model, and continuously driving the circulating pump to adjust the working frequency according to the real-time target working frequency so as to realize full-period regulation and control of the electrolyte flow. By establishing the flow fitting model, feedforward calculation and feedback adjustment of the flow can be realized without a flow meter, the cost of the system is reduced, the operation reliability of the flow battery is improved, and the service life of the flow battery is prolonged.

Description

Technical Field

[0001] This invention relates to the field of flow battery technology, and more specifically to a method and system for controlling the electrolyte flow rate in a flow battery. Background Technology

[0002] Flow batteries, as an important large-scale energy storage technology, have significant advantages such as long cycle life, high safety, and independent design of power and capacity. In flow battery systems, the electrolyte circulation flow rate is a key operating parameter that directly affects the battery's electrochemical performance and overall energy efficiency. Too low a flow rate leads to insufficient mass transfer of reactants within the stack, exacerbating concentration polarization and thus reducing energy efficiency; conversely, too high a flow rate significantly increases the power consumption of the pump driving the electrolyte circulation, similarly impairing the system's net output efficiency.

[0003] Currently, the common flow control method used in flow battery systems involves real-time monitoring of electrolyte flow rate using high-precision flow meters installed on the pipeline. The detected signal is fed back to the controller, which then adjusts the output frequency of the inverter to change the rotational speed of the circulating pump, thus achieving closed-loop flow control. However, industrial-grade high-precision flow meters are expensive, significantly increasing the total investment of the flow battery system due to their procurement, installation, and subsequent maintenance costs. Furthermore, flow meter feedback-based control is inherently a time-delay control. From the generation of flow deviation to flow meter detection, signal transmission, controller calculation, and finally pump speed adjustment, the entire control loop experiences a non-negligible time delay. This delay is particularly detrimental when the battery's state of charge (SOC) undergoes phased changes. The system cannot anticipate sudden changes in flow demand and can only respond passively, leading to flow overshoot or oscillations during adjustment. This not only increases the pump's ineffective power consumption but also reduces the system's operational stability. Therefore, it is necessary to provide a new flow battery electrolyte flow control method and system. Summary of the Invention

[0004] Based on the aforementioned problems in the existing technology, the purpose of this invention is to provide a method and system for controlling the electrolyte flow rate of a flow battery. By establishing a flow rate fitting model, feedforward and feedback control of the flow rate can be achieved without a flow meter, thereby reducing the cost of the system and improving the operational reliability and service life of the flow battery.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a method for controlling the electrolyte flow rate of a flow battery, comprising: Acquire initial parameter data for the flow battery, including SOC value, electrolyte temperature, inlet and outlet pressure difference, circulation pump power and operating frequency; The initial target flow rate of the electrolyte is determined based on the initial SOC value, initial operating mode, and preset electrolyte target flow rate model of the flow battery. Based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery, the initial target operating frequency of the circulating pump is obtained through a preset flow fitting model, and the circulating pump is driven to operate at the initial target operating frequency. Continuously collect real-time parameter data of the flow battery and update the real-time flow rate of the electrolyte through a flow fitting model; Based on the real-time SOC value of the flow battery and the current operating mode, the real-time target flow rate of the electrolyte is continuously updated. Based on the real-time target flow rate of the electrolyte, the real-time target operating frequency of the circulation pump is continuously updated through a flow fitting model, and the circulation pump is continuously driven to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of the electrolyte flow rate.

[0006] Furthermore, the target flow rate model for the electrolyte includes: When the flow battery is in charging mode, a first SOC value and a second SOC value are preset, wherein the first SOC value is less than the second SOC value. The first SOC value represents a low state of charge, and the second SOC value represents a high state of charge. When the SOC value of the flow battery is less than the first SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than or equal to the first SOC value and less than or equal to the second SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than the second SOC value, the target flow rate of the electrolyte is set to... .

[0007] Furthermore, the electrolyte target flow rate model also includes: When the flow battery is in discharge mode, a third SOC value and a fourth SOC value are preset. The third SOC value is less than the fourth SOC value. The third SOC value represents a low state of charge, and the fourth SOC value represents a high state of charge. When the SOC value of the flow battery is less than the third SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than or equal to the third SOC value and less than or equal to the fourth SOC value, the target flow rate of the electrolyte is set as follows: ; When the SOC value of the flow battery is greater than the fourth SOC value, the target flow rate of the electrolyte is set to... .

[0008] Furthermore, the flow fitting model is as follows:

[0009] in, Electrolyte flow rate This is a comprehensive proportional coefficient. f Let B be the operating frequency of the circulating pump, P be the power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. denoted as the inlet and outlet pressure difference, D as the exponential regression coefficient corresponding to the inlet and outlet pressure difference, T as the electrolyte temperature, and E as the exponential regression coefficient corresponding to the electrolyte temperature.

[0010] Furthermore, the step of determining the initial target operating frequency of the circulating pump based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery through a preset flow fitting model, and driving the circulating pump to operate at the initial target operating frequency, includes: When the flow battery starts up, the initial temperature of the electrolyte is obtained. Initial inlet and outlet pressure difference and the initial power of the circulating pump ; The initial target flow rate of the electrolyte Initial temperature of electrolyte Initial inlet and outlet pressure difference and the initial power of the circulating pump Substituting the values ​​into the flow fitting model, the initial target operating frequency of the circulating pump is calculated. ; set the initial target operating frequency of the circulating pump The command is sent to the frequency converter, which adjusts the operating frequency of the circulating pump to drive it at the initial target operating frequency. Stable operation ensures that the initial electrolyte flow rate is as close as possible to the initial target electrolyte flow rate.

[0011] Furthermore, based on the flow fitting model, the formula for calculating the initial target operating frequency of the circulating pump is derived as follows:

[0012] in, The initial target operating frequency of the circulating pump. This represents the initial target flow rate of the electrolyte. B is the comprehensive proportionality coefficient, and B is the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the initial power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. Let D be the initial inlet / outlet pressure difference, and D be the exponential regression coefficient corresponding to the inlet / outlet pressure difference. Let E be the initial temperature of the electrolyte, and E be the exponential regression coefficient corresponding to the electrolyte temperature.

[0013] Furthermore, the continuous acquisition of real-time parameter data of the flow battery and the updating of the real-time flow rate of the electrolyte through a flow fitting model include: Real-time parameter data for flow batteries includes real-time electrolyte temperature. Real-time inlet and outlet pressure difference Real-time power of the circulating pump and the real-time operating frequency of the circulating pump

[0014] The formula for calculating the real-time flow rate of the electrolyte is:

[0015] in, This represents the real-time flow rate of the electrolyte. This is a comprehensive proportional coefficient. Let B be the real-time operating frequency of the circulating pump, and let B be the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the real-time power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. The real-time inlet and outlet pressure difference is represented by D, which is the exponential regression coefficient corresponding to the inlet and outlet pressure difference. The real-time electrolyte temperature is given by E, where E is the exponential regression coefficient corresponding to the electrolyte temperature.

[0016] Furthermore, the step of continuously updating the real-time target flow rate of the electrolyte based on the real-time SOC value of the flow battery and the current operating mode; and continuously updating the real-time target operating frequency of the circulation pump based on the real-time target flow rate of the electrolyte using a flow fitting model, and continuously driving the circulation pump to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of the electrolyte flow rate includes: The battery management system continuously acquires the real-time SOC value of the flow battery and simultaneously confirms whether the current operating mode of the flow battery is charging or discharging.

[0017] The real-time SOC value and the current operating mode of the flow battery are continuously input into the electrolyte target flow rate model to update the real-time target flow rate of the electrolyte.

[0018] Based on the real-time target flow rate of the electrolyte and the continuously collected real-time parameter data of the flow battery, the real-time target operating frequency of the circulating pump is continuously updated through a flow fitting model.

[0019] The continuous drive circulation pump adjusts its operating frequency according to the real-time target operating frequency to achieve full-cycle control of electrolyte flow.

[0020] Furthermore, the formula for calculating the real-time target operating frequency is as follows:

[0021] in, The real-time target operating frequency of the circulating pump. This represents the real-time target flow rate of the electrolyte. B is the comprehensive proportionality coefficient, and B is the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the real-time power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. The real-time inlet and outlet pressure difference is represented by D, which is the exponential regression coefficient corresponding to the inlet and outlet pressure difference. The real-time electrolyte temperature is given by E, which is the exponential regression coefficient corresponding to the electrolyte temperature.

[0022] A flow battery electrolyte flow control system, applied to the above-mentioned flow battery electrolyte flow control method, the system comprising: The initial data acquisition module is used to acquire initial parameter data of the flow battery, including SOC value, electrolyte temperature, inlet and outlet pressure difference, power and operating frequency of the circulation pump; The initial flow calculation module is used to determine the initial target flow rate of the electrolyte based on the initial SOC value of the flow battery, the initial operating mode, and the preset electrolyte target flow rate model. The initial frequency control module is used to determine the initial target operating frequency of the circulating pump based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery through a preset flow fitting model, and drive the circulating pump to operate at the initial target operating frequency. The real-time flow calculation module is used to continuously collect real-time parameter data of the flow battery and update the real-time flow of the electrolyte through a flow fitting model. The real-time frequency control module is used to continuously update the real-time target flow rate of the electrolyte based on the real-time SOC value of the flow battery and the current operating mode; based on the real-time target flow rate of the electrolyte, it continuously updates the real-time target operating frequency of the circulation pump through a flow fitting model, and continuously drives the circulation pump to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle control of the electrolyte flow rate.

[0023] The beneficial effects of this invention are as follows: The electrolyte flow control method for flow batteries of this invention establishes a flow fitting model, resulting in a small error between the fitted flow rate and the actual flow rate. By utilizing data collected from existing sensors such as the power and operating frequency of the circulating pump, inlet and outlet pressures, and temperature data, the real-time flow rate can be estimated with high accuracy, saving the cost of using high-precision flow meters and simplifying the system structure. Based on the real-time SOC value and charging / discharging mode of the battery, differentiated target flow rates are set in segments, allowing for the pre-setting of appropriate flow targets before the SOC transition. A feedforward method is used to calculate the initial operating frequency of the circulating pump to quickly approach the target flow rate, and then feedback closed-loop fine-tuning is performed in conjunction with the real-time flow deviation. This avoids the large and frequent frequency adjustments caused by response lag in traditional methods, ensuring the circulating pump always operates stably near the high-efficiency zone, directly improving the overall energy efficiency of the system. By eliminating the signal delay of the flow meter and combining it with the SOC feedforward strategy, overshoot and fluctuations in flow control are reduced, making the operating frequency adjustment of the circulating pump smoother and with smaller amplitude, resulting in more stable electrolyte flow. This is beneficial for the equilibrium of the internal reaction of the battery stack, thereby improving the operational reliability and lifespan of the entire flow battery system. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] In the picture: Figure 1 A flowchart of a flow battery electrolyte flow control method provided in the first embodiment of the present invention; Figure 2 A schematic diagram of the structure of a flow battery provided for the first embodiment of the present invention; Figure 3 A fitting curve of electrolyte flow rate versus operating frequency of circulating pump provided for the first embodiment of the present invention; Figure 4 A fitting curve of electrolyte flow rate versus circulation pump power provided for the first embodiment of the present invention; Figure 5 A fitting curve of electrolyte flow rate versus inlet and outlet pressure difference of the circulating pump provided for the first embodiment of the present invention; Figure 6 A fitting curve of electrolyte flow rate versus electrolyte temperature provided for the first embodiment of the present invention; Figure 7 Accuracy verification and error distribution diagram of the flow fitting model provided for the first embodiment of the present invention.

[0026] Figure 8 A schematic diagram of the flow battery electrolyte flow control system provided for the second embodiment of the present invention; Figure 9This is a schematic diagram of the network-side server provided according to the third embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] First implementation method: The first embodiment of the present invention provides a method for controlling the electrolyte flow rate of a flow battery, comprising: acquiring initial parameter data of the flow battery, including SOC value, electrolyte temperature, inlet and outlet pressure difference, power and operating frequency of the circulation pump; determining an initial target flow rate of the electrolyte based on the initial SOC value of the flow battery, the initial operating mode, and a preset target flow rate model of the electrolyte; obtaining an initial target operating frequency of the circulation pump through a preset flow rate fitting model based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery, and driving the circulation pump to operate at the initial target operating frequency; continuously collecting real-time parameter data of the flow battery and updating the real-time flow rate of the electrolyte through the flow rate fitting model; continuously updating the real-time target flow rate of the electrolyte based on the real-time SOC value of the flow battery and the current operating mode; continuously updating the real-time target operating frequency of the circulation pump through the flow rate fitting model based on the real-time target flow rate of the electrolyte, and continuously driving the circulation pump to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of the electrolyte flow rate.

[0029] The electrolyte flow control method for flow batteries of this invention establishes a flow fitting model. This model uses the power and operating frequency of the circulating pump, inlet and outlet pressures, and temperature data to accurately estimate the real-time flow rate, saving the cost of high-precision flow meters and simplifying the system structure. Based on the battery's real-time SOC value and charging / discharging mode, differentiated target flow rates are set in segments, allowing for the pre-setting of appropriate flow targets before the SOC transition. A feedforward method is used to calculate the initial operating frequency of the circulating pump to quickly approach the target, and then closed-loop fine-tuning is performed based on the real-time flow deviation. This avoids the large and frequent frequency adjustments caused by response lag in traditional methods, ensuring the circulating pump always operates stably near the high-efficiency zone, directly improving the overall energy efficiency of the system. By eliminating the flow meter's signal delay and combining it with the SOC feedforward strategy, overshoot and fluctuations in flow control are reduced, resulting in smoother and smaller amplitude adjustments to the circulating pump's operating frequency. This leads to more stable electrolyte flow, promoting balanced reactions within the battery stack and thus improving the overall reliability and lifespan of the flow battery system.

[0030] The following uses a vanadium redox flow battery as an example to explain the implementation details of the electrolyte flow control method for this embodiment. The following details are provided for ease of understanding and are not essential for implementing this solution. The specific process of this embodiment is as follows: Figure 1 As shown.

[0031] The method for controlling the electrolyte flow rate of the flow battery includes: Step S1: Obtain initial parameter data of the flow battery, including SOC value (state of charge), electrolyte temperature, inlet and outlet pressure difference, power and operating frequency of the circulation pump.

[0032] Specifically, such as Figure 2 As shown, the flow battery 100 includes an electrolyte storage tank 110, a reactor stack 120, a circulation pipeline 130 connecting the electrolyte storage tank 110 and the reactor stack 120, a circulation pump 140 installed on the circulation pipeline 130, a frequency converter 150 connected to the circulation pump 140, a temperature sensor 160, and a first pressure sensor 170 and a second pressure sensor 180 respectively installed at the inlet and outlet of the circulation pump 140. The electrolyte storage tank 110 stores the electrolyte required for the operation of the flow battery, providing a stable electrolyte supply to the flow battery system. The reactor stack 120 is the core reaction site of the flow battery; the electrolyte flows inside the stack, converting electrical energy into chemical energy stored in the electrolyte during charging and converting chemical energy back into electrical energy during discharging. The circulation pipeline 130 enables the electrolyte to circulate between the electrolyte storage tank 110 and the reactor stack 120. The circulation pump 140 drives the continuous flow of the electrolyte in the circulation pipeline 130. The frequency converter 150 is used to adjust the operating frequency of the circulation pump 140, thereby controlling the operating speed of the circulation pump 140 and thus changing the electrolyte flow rate. The temperature sensor 160 is used to detect the electrolyte temperature in real time. The first pressure sensor 170 is used to detect the electrolyte pressure at the inlet of the circulation pump 140. The second pressure sensor 180 is used to detect the electrolyte pressure at the outlet of the circulation pump 140. The temperature and pressure sensors mentioned above are already equipped in the flow battery system. The flow battery provided in this embodiment does not add any new sensors, but saves on the need for a flow sensor. The figure only shows the electrolyte circulation pipeline on one side and the required electrolyte tank, circulation pump, frequency converter, and sensors. For liquid / liquid type flow batteries, the required configuration for the electrolyte on the other side is the same as this side.

[0033] The battery management system (BMS) of the flow battery 100 is used to detect and obtain the SOC value (state of charge) of the flow battery and whether the current operating mode of the flow battery is charging or discharging in real time.

[0034] The electrolyte temperature of the flow battery is obtained by a temperature sensor 160 installed on the circulation pipeline 130.

[0035] The inlet pressure value is collected by the first pressure sensor 170 at the inlet and the second pressure sensor 180 at the outlet of the circulating pump 140. and export pressure value And calculate the inlet pressure value. and export pressure value The difference between them yields the inlet and outlet pressure differential of the flow battery. .

[0036] The power of the circulating pump 140 is obtained through the power detection unit built into the circulating pump 140, and the operating frequency of the circulating pump is obtained through the frequency converter 150.

[0037] Step S2: Determine the initial target flow rate of the electrolyte based on the initial SOC value (state of charge) of the flow battery, the initial operating mode, and the preset target flow rate model of the electrolyte.

[0038] Specifically, the target flow rate model for the electrolyte is set based on the operating mode of the flow battery and its SOC (state of charge).

[0039] When the flow battery is in charging mode: A first SOC value and a second SOC value are preset, wherein the first SOC value is less than the second SOC value, the first SOC value represents a low charge state, and the second SOC value represents a high charge state.

[0040] When the SOC value of the flow battery is less than the first SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than or equal to the first SOC value and less than or equal to the second SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than the second SOC value, the target flow rate of the electrolyte is set to... ; in, When the SOC value of the flow battery is less than the first SOC value, a lower flow rate can meet the mass transfer requirements of the flow battery and significantly reduce the power consumption of the circulation pump. When the SOC value of the flow battery is greater than or equal to the first SOC value and less than or equal to the second SOC value, a moderate flow rate is required to enhance the mass transfer effect of the flow battery and prevent concentration polarization of the electrolyte. When the SOC value of the flow battery is greater than the second SOC value, the flow battery is close to a fully charged state, and a higher flow rate is required to enhance the mass transfer of the flow battery and avoid side reactions such as hydrogen evolution.

[0041] As an example, the first SOC value is set at 30%, and the second SOC value is set at 80%. Target flow rate of the electrolyte. Pick Target flow rate of electrolyte Pick Target flow rate of electrolyte Pick .

[0042] When the flow battery is operating in discharge mode: A third SOC value and a fourth SOC value are preset, wherein the third SOC value is less than the fourth SOC value. The third SOC value represents a low charge state, and the fourth SOC value represents a high charge state.

[0043] When the SOC value of the flow battery is less than the third SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than or equal to the third SOC value and less than or equal to the fourth SOC value, the target flow rate of the electrolyte is set as follows: ; When the SOC value of the flow battery is greater than the fourth SOC value, the target flow rate of the electrolyte is set to... ; Among them, the target flow rate of the electrolyte under discharge conditions is set in conjunction with the mass transfer requirements of the discharge stage, and the required target flow rate is set accordingly. , and This ensures stable energy efficiency during the discharge process.

[0044] To determine the initial target flow rate of the electrolyte, specifically, when the flow battery starts up, the initial SOC value of the flow battery is obtained through the battery management system (BMS), and the initial operating mode (charging or discharging) is confirmed. Then, the initial SOC value and the initial operating mode are substituted into the electrolyte target flow rate model to determine the initial target flow rate of the electrolyte when the system starts up. .

[0045] As an example, when a flow battery starts up, if the initial SOC value is less than the first SOC value, the operating mode is charging. Therefore, the initial target flow rate... = .

[0046] Step S3: Based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery, the initial target operating frequency of the circulating pump is obtained through a preset flow fitting model, and the circulating pump is driven to operate at the initial target operating frequency.

[0047] Specifically, based on fluid mechanics and the characteristics of circulating pumps, a flow fitting model is established according to the power relationship between electrolyte flow rate and flow battery parameter data.

[0048] Specifically, based on fluid mechanics principles and the characteristics of circulating pumps, there is a nonlinear relationship between electrolyte flow rate and electrolyte temperature, inlet and outlet pressure difference, circulating pump power, and operating frequency. Using extensive preliminary experimental data, a flow rate fitting model without a flow meter is established using multiple regression analysis:

[0049] in, Electrolyte flow rate This is a comprehensive proportional coefficient. f Let B be the operating frequency of the circulating pump, P be the power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. denoted as the inlet and outlet pressure difference, D as the exponential regression coefficient corresponding to the inlet and outlet pressure difference, T as the electrolyte temperature, and E as the exponential regression coefficient corresponding to the electrolyte temperature.

[0050] It should be noted that the comprehensive ratio coefficient The specific values ​​of the exponential regression coefficient B corresponding to the operating frequency of the circulation pump, the exponential regression coefficient C corresponding to the power of the circulation pump, the exponential regression coefficient D corresponding to the inlet and outlet pressure difference, and the exponential regression coefficient E corresponding to the electrolyte temperature were obtained by performing multiple regression fitting on the experimental data of the flow battery (covering different electrolyte flow rates, electrolyte temperatures, inlet and outlet pressure differences, circulation pump power, and operating frequencies). Ultimately, this enabled the flow fitting model to accurately describe the relationship between flow rate and each parameter.

[0051] Specifically, based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery, the initial target operating frequency of the circulation pump is obtained through a preset flow fitting model, and the circulation pump is driven to operate at the initial target operating frequency, including the following steps: Step S31: When the flow battery starts up, obtain the initial temperature of the electrolyte. Initial inlet and outlet pressure difference and the initial power of the circulating pump .

[0052] Step S32, set the initial target flow rate of the electrolyte. Initial temperature of electrolyte Initial inlet and outlet pressure difference and the initial power of the circulating pump Substituting the values ​​into the flow fitting model, the initial target operating frequency of the circulating pump is calculated. .

[0053] The formula for calculating the initial target operating frequency of the circulating pump, derived from the flow fitting model, is as follows:

[0054] in, The initial target operating frequency of the circulating pump. This represents the initial target flow rate of the electrolyte. B is the comprehensive proportionality coefficient, and B is the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the initial power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. Let D be the initial inlet / outlet pressure difference, and D be the exponential regression coefficient corresponding to the inlet / outlet pressure difference. Let be the initial temperature of the electrolyte, and E be the exponential regression coefficient corresponding to the electrolyte temperature.

[0055] Step S33: Set the initial target operating frequency of the circulating pump. The command is sent to the frequency converter, which adjusts the operating frequency of the circulating pump to drive it at the initial target operating frequency. Stable operation ensures that the initial flow rate of the electrolyte is as close as possible to the initial target flow rate of the electrolyte.

[0056] Step S4: Continuously collect real-time parameter data of the flow battery and update the real-time flow rate of the electrolyte through a flow fitting model.

[0057] Specifically, it includes the following steps: Step S41, the real-time parameter data of the flow battery includes the real-time electrolyte temperature. Real-time inlet and outlet pressure difference Real-time power of the circulating pump and the real-time operating frequency of the circulating pump .

[0058] Step S42, the formula for calculating the real-time flow rate of the electrolyte is:

[0059] in, This represents the real-time flow rate of the electrolyte. This is a comprehensive proportional coefficient. Let B be the real-time operating frequency of the circulating pump, and let B be the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the real-time power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. The real-time inlet and outlet pressure difference is represented by D, which is the exponential regression coefficient corresponding to the inlet and outlet pressure difference. The real-time electrolyte temperature is given by E, which is the exponential regression coefficient corresponding to the electrolyte temperature.

[0060] Step S5: Based on the real-time SOC value of the flow battery and the current operating mode, continuously update the real-time target flow rate of the electrolyte; based on the real-time target flow rate of the electrolyte, continuously update the real-time target operating frequency of the circulation pump through the flow fitting model, and continuously drive the circulation pump to adjust the operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of the electrolyte flow rate.

[0061] Specifically, it includes: Step S51: Continuously acquire the real-time SOC value of the flow battery through the battery management system (BMS), and confirm whether the current working mode of the flow battery is charging or discharging.

[0062] Step S52: Continuously input the real-time SOC value and the current operating mode of the flow battery into the electrolyte target flow model to update the real-time target flow rate of the electrolyte. When the SOC value changes and crosses a preset threshold (such as the first, second, third, or fourth SOC value), or when the current operating mode (charging or discharging) changes, the real-time target flow rate of the electrolyte will change.

[0063] Step S53: Based on the real-time target flow rate of the electrolyte and the continuously collected real-time parameter data of the flow battery, the real-time target operating frequency of the circulating pump is continuously updated through the flow fitting model.

[0064] Specifically, the formula for calculating the real-time target operating frequency is:

[0065] in, The real-time target operating frequency of the circulating pump. This represents the real-time target flow rate of the electrolyte. B is the comprehensive proportionality coefficient, and B is the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the real-time power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. The real-time inlet and outlet pressure difference is represented by D, which is the exponential regression coefficient corresponding to the inlet and outlet pressure difference. The real-time electrolyte temperature is given by E, which is the exponential regression coefficient corresponding to the electrolyte temperature.

[0066] Step S54: The circulating pump is continuously driven to adjust the operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of electrolyte flow.

[0067] This invention discloses a flow battery electrolyte flow control method. It establishes a flow fitting model that eliminates the need for a flow meter. This model uses the power and operating frequency of the circulating pump, inlet and outlet pressures, and temperature data to accurately estimate real-time flow, saving the cost of using a high-precision flow meter and simplifying the system structure. Based on the battery's real-time SOC value and charging / discharging mode, differentiated target flow rates are set in segments. Appropriate flow targets can be preset before the SOC transition. A feedforward method is used to calculate the initial operating frequency of the circulating pump to quickly approach the target, and then closed-loop fine-tuning is performed based on real-time flow deviations. This avoids the large and frequent frequency adjustments caused by response lag in traditional methods, ensuring the circulating pump always operates stably near the high-efficiency zone, directly improving the overall energy efficiency of the system. By eliminating the flow meter's signal delay and combining it with the SOC feedforward strategy, overshoot and fluctuations in flow control are reduced, resulting in smoother and smaller amplitude adjustments to the circulating pump's operating frequency. This leads to more stable electrolyte flow, promoting balanced reactions within the battery stack and improving the overall reliability and lifespan of the flow battery system.

[0068] Example 1 This example details the process of establishing the flow fitting model (i.e., the model described in step S3), its specific parameters, and the verification results.

[0069] Construct a complete vanadium redox flow battery testing system, including an electrolyte storage tank, reactor stack, circulation pipeline, circulation pump, frequency converter, standard high-precision turbine flow meter, pump inlet and outlet pressure sensors, and pipeline temperature sensors. (Refer to...) Figure 2 The only difference is the addition of a standard high-precision turbine flow meter to the circulation pipeline. Under different operating conditions of the system, the following data are collected simultaneously: the electrolyte flow rate measured by the standard flow meter, the operating frequency of the circulation pump, the circulation pump power calculated from the voltage and current fed back by the frequency converter through the power detection unit of the circulation pump, the pressure difference between the inlet and outlet of the circulation pump, and the electrolyte temperature.

[0070] The collected data is preprocessed, including outlier removal and data smoothing.

[0071] Based on fluid mechanics principles and pump characteristic curves, a nonlinear power relationship exists between flow rate and various parameters. The following model is used for fitting:

[0072] in, Electrolyte flow rate, unit: ; This is a comprehensive proportionality coefficient, with units of 1. ; f The operating frequency of the circulating pump, in units of ; Bis the exponential regression coefficient corresponding to the operating frequency of the circulating pump, which is dimensionless; P The power of the circulating pump is expressed in units of... ; C The exponential regression coefficient corresponding to the power of the circulating pump is dimensionless. The pressure difference between the inlet and outlet is expressed in units of... ; D is the exponential regression coefficient corresponding to the pressure difference between import and export, which is dimensionless; T The electrolyte temperature is expressed in Celsius and is dimensionless. E is the exponential regression coefficient corresponding to the electrolyte temperature and is also dimensionless.

[0073] like Figure 3-6 As shown, the preprocessed experimental data were substituted into the above model, and a multivariate nonlinear regression analysis method was used for fitting. Through least squares optimization, a set of model coefficients was obtained that minimized the error between the calculated and measured values. The final determined model parameters are: The overall proportionality coefficient A = 4.12256 The exponential regression coefficients corresponding to the operating frequency of the circulating pump are B = 0.40322; the exponential regression coefficients corresponding to the power of the circulating pump are C = 0.16597; the exponential regression coefficients corresponding to the inlet and outlet pressure difference are D = 0.10517; and the exponential regression coefficients corresponding to the electrolyte temperature are E = 0.01821. Therefore, the specific flow rate fitting model is as follows:

[0074] in, Electrolyte flow rate, unit: ; The comprehensive proportionality coefficient is set to 4.12256, and the unit is... ; f The operating frequency of the circulating pump, in units of P represents the power of the circulating pump, measured in units of... ; The pressure difference between the inlet and outlet is expressed in units of... T represents the electrolyte temperature, expressed in Celsius, and is dimensionless.

[0075] The model was validated using a separate set of independent experimental data not involved in the modeling. The error between the flow rate calculated by the model and the flow rate measured by a standard flow meter was calculated. Figure 7As shown, statistical results indicate that the prediction error for over 95% of the data points is within ±2%, meeting the accuracy requirements for industrial control. Furthermore, the coefficient of determination R² = 0.99131 > 0.98, indicating that the model can explain over 99.1% of the flow data variation, demonstrating extremely high goodness of fit and accuracy. This means that the model provided in this application can accurately calculate the electrolyte flow rate using data from existing system sensors, eliminating the need for flow sensors.

[0076] like Figure 8 As shown, the second embodiment of the present invention provides a flow battery electrolyte flow control system, including: an initial data acquisition module 201, an initial flow calculation module 202, an initial frequency control module 203, a real-time flow calculation module 204, and a real-time frequency adjustment module 205.

[0077] Specifically, the initial data acquisition module 201 is used to acquire initial parameter data of the flow battery, including SOC value, electrolyte temperature, inlet and outlet pressure difference, power and operating frequency of the circulation pump; the initial flow calculation module 202 is used to determine the initial target flow rate of the electrolyte based on the initial SOC value of the flow battery, the initial operating mode, and a preset electrolyte target flow rate model; the initial frequency control module 203 is used to derive the initial target operating frequency of the circulation pump through a preset flow fitting model based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery, and drive the circulation pump to operate at the initial target operating frequency; the real-time flow calculation module 204 is used to continuously acquire real-time parameter data of the flow battery and update the real-time flow rate of the electrolyte through the flow fitting model; the real-time frequency control module 205 is used to continuously update the real-time target flow rate of the electrolyte based on the real-time SOC value of the flow battery and the current operating mode; based on the real-time target flow rate of the electrolyte, it continuously updates the real-time target operating frequency of the circulation pump through the flow fitting model, and continuously drives the circulation pump to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle control of the electrolyte flow rate.

[0078] It is not difficult to see that this embodiment is a system implementation corresponding to the first embodiment, and this embodiment can be implemented in conjunction with the first embodiment. The relevant technical details mentioned in the first embodiment are still valid in this embodiment, and will not be repeated here to reduce repetition. Accordingly, the relevant technical details mentioned in this embodiment can also be applied to the first embodiment.

[0079] It is worth mentioning that all modules involved in this embodiment are logical modules. In practical applications, a logical unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. Furthermore, to highlight the innovative aspects of this invention, this embodiment does not introduce units that are not closely related to solving the technical problem proposed by this invention; however, this does not mean that other units are absent from this embodiment.

[0080] The third embodiment of the present invention relates to a network-side server, such as... Figure 9 As shown, it includes at least one processor 302; and a memory 301 communicatively connected to at least one processor 302; wherein the memory 301 stores instructions executable by at least one processor 302, the instructions being executed by at least one processor 302 to enable at least one processor 302 to perform the above-described data processing method.

[0081] The memory 301 and processor 302 are connected via a bus, which may include any number of interconnecting buses and bridges. The bus connects various circuits of one or more processors 302 and memory 301 together. The bus can also connect various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. A bus interface provides an interface between the bus and the transceiver. The transceiver can be a single element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by processor 302 is transmitted over a wireless medium via an antenna, which further receives data and transmits it to processor 302.

[0082] Processor 302 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory 301 can be used to store data used by processor 302 during operation.

[0083] The fourth embodiment of the present invention relates to a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the flow battery electrolyte flow control method of the first embodiment.

[0084] That is, those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0085] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling the electrolyte flow rate in a flow battery, characterized in that, include: Acquire initial parameter data for the flow battery, including SOC value, electrolyte temperature, inlet and outlet pressure difference, circulation pump power and operating frequency; The initial target flow rate of the electrolyte is determined based on the initial SOC value, initial operating mode, and preset electrolyte target flow rate model of the flow battery. Based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery, the initial target operating frequency of the circulating pump is obtained through a preset flow fitting model, and the circulating pump is driven to operate at the initial target operating frequency. Continuously collect real-time parameter data of the flow battery and update the real-time flow rate of the electrolyte through a flow fitting model; The real-time target flow rate of the electrolyte is continuously updated based on the real-time SOC value of the flow battery and the current operating mode. Based on the real-time target flow rate of the electrolyte, the real-time target operating frequency of the circulating pump is continuously updated through a flow fitting model, and the circulating pump is continuously driven to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of the electrolyte flow rate.

2. The method for controlling the electrolyte flow rate of a flow battery according to claim 1, characterized in that, The target flow rate model for the electrolyte includes: When the flow battery is in charging mode: A first SOC value and a second SOC value are preset, wherein the first SOC value is less than the second SOC value, the first SOC value represents a low state of charge, and the second SOC value represents a high state of charge. When the SOC value of the flow battery is less than the first SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than or equal to the first SOC value and less than or equal to the second SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than the second SOC value, the target flow rate of the electrolyte is set to... .

3. The method for controlling the electrolyte flow rate of a flow battery according to claim 2, characterized in that, The electrolyte target flow rate model also includes: When the flow battery is operating in discharge mode: A third SOC value and a fourth SOC value are preset, wherein the third SOC value is less than the fourth SOC value, the third SOC value represents a low charge state, and the fourth SOC value represents a high charge state. When the SOC value of the flow battery is less than the third SOC value, the target flow rate of the electrolyte is set to... ; When the SOC value of the flow battery is greater than or equal to the third SOC value and less than or equal to the fourth SOC value, the target flow rate of the electrolyte is set as follows: ; When the SOC value of the flow battery is greater than the fourth SOC value, the target flow rate of the electrolyte is set to... .

4. The method for controlling the electrolyte flow rate of a flow battery according to claim 1, characterized in that, The flow fitting model is as follows: in, Electrolyte flow rate, This is a comprehensive proportional coefficient. f Let B be the operating frequency of the circulating pump, P be the power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. denoted as the inlet and outlet pressure difference, D as the exponential regression coefficient corresponding to the inlet and outlet pressure difference, T as the electrolyte temperature, and E as the exponential regression coefficient corresponding to the electrolyte temperature.

5. The method for controlling the electrolyte flow rate of a flow battery according to claim 1, characterized in that, The step of determining the initial target operating frequency of the circulating pump based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery through a preset flow fitting model, and driving the circulating pump to operate at the initial target operating frequency includes: When the flow battery starts up, the initial temperature of the electrolyte is obtained. Initial inlet and outlet pressure difference and the initial power of the circulating pump ; The initial target flow rate of the electrolyte Initial temperature of electrolyte Initial inlet and outlet pressure difference and the initial power of the circulating pump Substituting the values ​​into the flow fitting model, the initial target operating frequency of the circulating pump is calculated. ; set the initial target operating frequency of the circulating pump The command is sent to the frequency converter, which adjusts the operating frequency of the circulating pump to drive it at the initial target operating frequency. Stable operation.

6. The method for controlling the electrolyte flow rate of a flow battery according to claim 5, characterized in that, The formula for calculating the initial target operating frequency of the circulating pump, derived from the flow fitting model, is as follows: in, The initial target operating frequency of the circulating pump. This represents the initial target flow rate of the electrolyte. B is the comprehensive proportionality coefficient, and B is the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the initial power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. Let D be the initial inlet / outlet pressure difference, and D be the exponential regression coefficient corresponding to the inlet / outlet pressure difference. Let be the initial temperature of the electrolyte, and E be the exponential regression coefficient corresponding to the electrolyte temperature.

7. The method for controlling the electrolyte flow rate of a flow battery according to claim 1, characterized in that, The continuous acquisition of real-time parameter data of the flow battery and the updating of the real-time electrolyte flow rate through a flow fitting model include: Real-time parameter data for flow batteries includes real-time electrolyte temperature. Real-time inlet and outlet pressure difference Real-time power of the circulating pump and the real-time operating frequency of the circulating pump ; The formula for calculating the real-time flow rate of the electrolyte is: in, This represents the real-time flow rate of the electrolyte. This is a comprehensive proportional coefficient. Let B be the real-time operating frequency of the circulating pump, and let B be the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the real-time power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. The real-time inlet and outlet pressure difference is represented by D, which is the exponential regression coefficient corresponding to the inlet and outlet pressure difference. The real-time electrolyte temperature is given by E, which is the exponential regression coefficient corresponding to the electrolyte temperature.

8. The method for controlling the electrolyte flow rate of a flow battery according to claim 1, characterized in that, The system continuously updates the real-time target flow rate of the electrolyte based on the real-time SOC value of the flow battery and the current operating mode. Based on the real-time target flow rate of the electrolyte, the real-time target operating frequency of the circulating pump is continuously updated through a flow fitting model, and the circulating pump is continuously driven to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle regulation of the electrolyte flow rate, including: Continuously acquire the real-time SOC value of the flow battery and confirm the current operating mode of the flow battery. The real-time SOC value and the current operating mode of the flow battery are continuously substituted into the electrolyte target flow model to update the real-time target flow of the electrolyte. Based on the real-time target flow rate of the electrolyte and the continuously collected real-time parameter data of the flow battery, the real-time target operating frequency of the circulating pump is continuously updated through a flow fitting model. The continuous drive circulation pump adjusts its operating frequency according to the real-time target operating frequency to achieve full-cycle control of electrolyte flow.

9. The method for controlling the electrolyte flow rate of a flow battery according to claim 8, characterized in that, The formula for calculating the real-time target operating frequency is: in, The real-time target operating frequency of the circulating pump. This represents the real-time target flow rate of the electrolyte. B is the comprehensive proportionality coefficient, and B is the exponential regression coefficient corresponding to the operating frequency of the circulating pump. Let be the real-time power of the circulating pump, and C be the exponential regression coefficient corresponding to the power of the circulating pump. The real-time inlet and outlet pressure difference is represented by D, which is the exponential regression coefficient corresponding to the inlet and outlet pressure difference. The real-time electrolyte temperature is given by E, which is the exponential regression coefficient corresponding to the electrolyte temperature.

10. A flow battery electrolyte flow control system, characterized in that, The system, applied to the flow battery electrolyte flow control method according to any one of claims 1-9, comprises: The initial data acquisition module is used to acquire initial parameter data of the flow battery, including SOC value, electrolyte temperature, inlet and outlet pressure difference, power and operating frequency of the circulation pump; The initial flow calculation module is used to determine the initial target flow rate of the electrolyte based on the initial SOC value of the flow battery, the initial operating mode, and the preset electrolyte target flow rate model. The initial frequency control module is used to determine the initial target operating frequency of the circulating pump based on the initial target flow rate of the electrolyte and the initial parameter data of the flow battery through a preset flow fitting model, and drive the circulating pump to operate at the initial target operating frequency. The real-time flow calculation module is used to continuously collect real-time parameter data of the flow battery and update the real-time flow of the electrolyte through a flow fitting model. The real-time frequency control module is used to continuously update the real-time target flow rate of the electrolyte based on the real-time SOC value of the flow battery and the current operating mode; based on the real-time target flow rate of the electrolyte, it continuously updates the real-time target operating frequency of the circulation pump through a flow fitting model, and continuously drives the circulation pump to adjust its operating frequency according to the real-time target operating frequency to achieve full-cycle control of the electrolyte flow rate.

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